The objective of this study is to determine the efficacy of periodic dental bitewing examinations in relation to frequency, cost to the patient, distribution by various population characteristics, yield of information and contribution to diagnosis and treatment of interproximal caries. This will be studied retrospectively in a fluoridated community using the records of at least 7 years standing from 25 dentists selected at random in the community. Dentists will be members of good standing of the local dental society who have volunteered to cooperate and will have been in practice for at least 12 years. The population of patients to be studied will be balanced in respect to age, sex, caries history, occupation of the patient or the patient's family and length of time the patient has lived in the community. The radiographs will be rated by independent examiners. Specific parameters that will be evaluated by the raters will be the quality of the radiographs, presence and absence of interproximal caries and restorations and the correlation between these findings and treatment patterns of the participating dentists.